Embodiments relate to a light emitting device, a light emitting device package and a lighting system including the same.
Nitride semiconductors are attracting much attention for the fields of optical devices and high-power electronic devices because of their high thermal stability and wide band gap energy. In particular, blue light emitting devices (LEDs), green LEDs, and UV LEDs that use nitride semiconductors have been commercialized and are being widely used.
According to the related art, not only GaN substrates but also heterogeneous substrates formed of different materials (e.g., silicon, sapphire, and silicon carbide (SiC)) are used to grow GaN epitaxial layers. When GaN-based materials are grown on such heterogeneous substrates, many defects such as threading dislocations (TD) are included in the grown thin layer due to the mismatches between crystal lattice coefficients and thermal expansion coefficients.
Also, according to the related art, a dry etching or wet etching-based isolation process is used to provide the isolation between LED chips. However, the LED may be damaged by plasma or chemicals during the etching-based isolation process, thereby degrading the chip reliability.